PHYSICS Frintin- PHYSICS Friction Two 1) The coefficient of static friction for a brick on concrete is found to be 0.82. The mass of the brick is 4 kg. What would happen if an applied (sideways pushing) force was a. 28 N 6. 31 N c. 32.2 N 2) If the coefficient of kinetic friction was .57 for the brick in problem (1), and the applied force was 35 N, a. What is the force of friction acting on the brick? b. What is the net force acting on the brick? c. What is the acceleration of the brick? d. How far will the brick travel in 10 seconds if it starts from rest? 3) The coefficient of static friction for a 10 kg metal block on concrete is 0.72, and the coefficient of kinetic friction is 0.38. a. What is the minimum force required for the mass to be moved from rest. b. Once the mass begins to move, the problem becomes a kinetic friction problem. The applied force is held constant throughout this problem. When the mass is moving, what is the force of friction? c. What is the net force acting on the mass while it is moving? d. What is the acceleration of the mass while it is moving? 4) Opper the physics dog sees a large dinosaur bone, and attempts to drag it into his physics dog house. He grabs the bone with his mighty teeth, and pulls it at a constant velocity of 1245 m/s with a force of 3456 N. The mass of the bone is 12,000 kg. a. Is this a static or kinetic friction problem? b. Why doesn't the bone accelerate? c. What is the net force acting on the bone? d. What is the force of friction acting on the bone? e. What is the coefficient of friction between the bone and the ground? f. Suddenly, a giant Ringosaurus with a mass of 10,000 kg jumps on top of the bone. What force must Opper pull with in order to keep the bone moving at a constant speed? 5) A rubber band launcher applies a force of 45 N on a bowling ball with a mass of 6 kg. The launcher acts on the ball through a distance of 2 m and the coefficient of friction between the ball and the launcher is = 0.59. a. Calculate the force of friction between the ball and the launcher. b. What is the net force acting on the ball? c. What is the acceleration of the ball while on the launcher? d. What is the final velocity of the ball when it reaches the end of the launcher if it starts from rest? e. The launcher has been placed on a table that is 1.8 m high. When the mass reaches the end of the table, it flies off and lands on the ground. What will the horizontal displacement of the bowling ball be when it hits the ground? 1) nothing nothing 2) 22.34 N 12.66 N 3. 16 m/s2 158.2 m 3) 70.56 N 37.24 N 33.32 N 3.33 m/s2 4) kinetic it's at equilibrium ON -3456 N 0.03 6468 N 5) 34.69 N 10.31 N 1.72 m/s2 2.62 m/s 1.59 m